If there are multiple engagements targeting the same group of users on the same page, the users will see the engagements on the order of priority of the engagements. On the engagements list page, the engagements at the top are of highest priority, and the engagements on the bottom are of lowest priority.
If a user is shown 2 engagements on the same page, the user will see the engagement of higher priority today and will see the other engagement next session.
Multiple engagement display is dependent on the frequency of the engagement and the throttle of the global user settings. Higher frequency will increase the number of sessions that the engagement will be displayed. Higher throttle will increase the number of engagements that will be displayed per session.